How to design fluorine plastic lining butterfly valve?

Fluoroplastic lined butterfly valve design: 1, Overview: With the rapid development of the modern petrochemical industry, some of the media used in special conditions are highly corrosive, even stainless steel valves and rubber lining, enamel valves have also been Can not meet the needs. If the use of Hastelloy, Monel or Alloy No. 20 as the valve material, due to its large amount of Ni, Cr, Ti, Mo, Nb and Pt and other rare metals, its limited resources, expensive. According to the results of modern science and technology, fluorine plastic molecular structure with fluorocarbon bond and its shielding effect, with excellent corrosion resistance, high (low) temperature, non-sticking and electrical insulation, almost to resist all chemical media (Including hydrofluoric acid, concentrated sulfuric acid and aqua regia) corrosion. Fluoroplastics plastic processing principle, the fluorine plastic lined in the ordinary steel shell to cut off the metal contact with the strong corrosive media, both to solve the problem of low strength and can not withstand the high pressure of fluoroplastic, but also solved the Steel material is not resistant to corrosion problems. Fluoroplastic-lined valves have excellent heat and cold resistance, excellent electrical insulation and excellent chemical stability, and are resistant to all types of strong acids, strong bases and strong oxidizers. Low friction and very good self-lubricity , Long-term use in the range of - 195 ~ 200 ℃. 2) Structure and design: Structure and main parts name: 1) Drive unit 2 Dust seal 3 O-ring 4 Disc 5 Butterfly lining 6 Seat lining 7 Valve body 2) Scope of application: Fluorine plastic lining butterfly valve Nominal pressure PN116 (fluoroplastic pressure up to 215MPa). DN50 ~ 1 200. Valve temperature by the choice of different materials (metal materials and non-metallic materials) can withstand the temperature comprehensive assessment. Such as steel lined fluorine plastic (WCB + F46) material, the use of temperature - 29 ~ 150 ℃. Limit the maximum value does not exceed 150 ℃. Suitable medium for low viscosity acids and bases and other corrosive media, mainly refers to acidic, alkaline, organic and inorganic solvents and other corrosive media. Low viscosity is relatively high concentration of granular media, the fluorine plastic liner valves should try to avoid the use of solid particulate media. 3. Test Methods: (1) Temperature: The test temperature is measured from room temperature to the temperature range of liquid nitrogen. The temperature is measured by a thermocouple thermometer. The temperature electric signal is measured by a digital multimeter. The measured temperature is collected and input into the measurement and control computer and displayed on the computer interface. By the computer automatically record and save. At the same time, the computer sends the temperature measurement to the temperature display on the instrument panel for on-site display. Imported pump industrial washing machine (2) Pressure: Test pressure measurement range of 0 ~ 10M Pa. The use of pointer precision pressure gauge and digital pressure gauge on the instrument panel on-site display of system pressure at the same time, the use of pressure transmitters to measure system pressure and converted to voltage signals measured by the digital multimeter to collect and input measurement and control computer , Displayed on the computer interface and automatically recorded and saved by the computer. (3) Level: In order to ensure high liquid nitrogen level to meet the valve test requirements, the use of differential pressure transmitter to measure the liquid level. Measurement of electrical signals through the digital multimeter measurement, acquisition and input to the computer for display, and reminded filling liquid nitrogen and stop liquid nitrogen filling operation. (4) flow: According to the different forms of valve sealing, the valve allows the amount of leakage is different. Soft seal structure of the valve, the amount of leakage should be zero. For hard-sealed valve itself is allowed to have a certain amount of leakage. Based on the above, two devices for measuring the flow rate are provided, one of which is a low-flow meter for measuring the leakage of a hard-sealed valve or a soft-sealed valve that allows a certain amount of leakage in a relatively abnormal working state. For a small amount of leakage, as the general flowmeter has been unable to detect, you need to observe and count the number of open-ended bubbles in the water to measure the number of leaks. Using computer data acquisition system to record the number of electrical pulses to achieve automatic counting. 4 Conclusion: Based on computer data acquisition system of low-temperature valve performance test device, you can thermocouple, pressure sensor, level sensor and flowmeter of each signal, the pre-processing input to the computer through the data acquisition software Data display, storage and printing, but also according to the relevant parameters set to control the liquid nitrogen tank self-pressurization system of low temperature test tank for liquid nitrogen. The test system uses centralized data monitoring, which not only enables the computer to issue commands to operate automatically, improve work efficiency, timeliness, accuracy and security of operation, but also facilitate the unified data storage and management. This article Keywords: butterfly valve